This invention pertains to new and improved electrical resistors. More specifically it pertains to electrical resistors which are capable of being utilized in some applications as RC networks and which can also be utilized as normal resistors.
As the related electrical and electronic fields have developed many different resistors have been developed for many different uses and applications. Frequently such resistors are created or manufactured by locating a film or coating serving as a resistance element on an appropriate dielectric substrate so that the resistance film extends between electrical terminals located on the substrate. Frequently such resistors are manufactured as an integral part of a circuit "board" or "structure" containing a variety of different terminals, conductors extending between such terminals and such resistance elements. At times such circuit "boards" or "structures" may also contain inductors and capacitors.
Many of such circuit "boards" have been constructed utilizing an electrically non-conductive substrate formed of an appropriate organic resin composition. Although such substrates have proved to be very utilitarian for use in connection with circuit components as noted, they are somewhat disadvantageous for certain applications because of the fact that comparatively elevated temperatures will detrimentally affect any organic material. To a degree this complication can be alleviated by the use of an electrically non-conductive ceramic substrate. The use of such ceramic substrates in many applications is disadvantageous because of their weight and because of the fact that they are somewhat prone to physical damage.
A recognition of these factors has resulted in a resurgence of past techniques of utilizing steel coated with a dielectric material as a substrate for circuit structures as indicated in the preceding discussion. The steel possesses good physical characteristics which are apt to preclude damage. Further, so long as the dielectric used with the steel is ceramic, the entire substrate can withstand comparatively high temperatures such as would normally damage various types of essentially organic substrates. Circuit boards or structures as indicated in this discussion normally utilize many different resistors, conductors and terminals as indicated in the preceding discussion. They cannot be used as simple, effective RC networks although they can be and frequently are used as more complex networks.